ipc/glue/Neutering.h

   1 /* -*- Mode: C++; tab-width: 8; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
   2 /* vim: set ts=8 sts=2 et sw=2 tw=80: */
   3 /* This Source Code Form is subject to the terms of the Mozilla Public
   4  * License, v. 2.0. If a copy of the MPL was not distributed with this
   5  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */
   6
   7 #ifndef mozilla_ipc_Neutering_h
   8 #define mozilla_ipc_Neutering_h
   9
  10 /**
  11  * This header declares RAII wrappers for Window neutering. See
  12  * WindowsMessageLoop.cpp for more details.
  13  */
  14
  15 namespace mozilla {
  16 namespace ipc {
  17
  18 /**
  19  * This class is a RAII wrapper around Window neutering. As long as a
  20  * NeuteredWindowRegion object is instantiated, Win32 windows belonging to the
  21  * current thread will be neutered. It is safe to nest multiple instances of
  22  * this class.
  23  */
  24 class MOZ_RAII NeuteredWindowRegion {
  25  public:
  26   explicit NeuteredWindowRegion(bool aDoNeuter);
  27   ~NeuteredWindowRegion();
  28
  29   /**
  30    * This function clears any backlog of nonqueued messages that are pending for
  31    * the current thread.
  32    */
  33   void PumpOnce();
  34
  35  private:
  36   bool mNeuteredByThis;
  37 };
  38
  39 /**
  40  * This class is analagous to MutexAutoUnlock for Mutex; it is an RAII class
  41  * that is to be instantiated within a NeuteredWindowRegion, thus temporarily
  42  * disabling neutering for the remainder of its enclosing block.
  43  * @see NeuteredWindowRegion
  44  */
  45 class MOZ_RAII DeneuteredWindowRegion {
  46  public:
  47   explicit DeneuteredWindowRegion();
  48   ~DeneuteredWindowRegion();
  49
  50  private:
  51   bool mReneuter;
  52 };
  53
  54 class MOZ_RAII SuppressedNeuteringRegion {
  55  public:
  56   explicit SuppressedNeuteringRegion();
  57   ~SuppressedNeuteringRegion();
  58
  59   static inline bool IsNeuteringSuppressed() { return sSuppressNeutering; }
  60
  61  private:
  62   bool mReenable;
  63
  64   static bool sSuppressNeutering;
  65 };
  66
  67 }  // namespace ipc
  68 }  // namespace mozilla
  69
  70 #endif  // mozilla_ipc_Neutering_h